NCI Definition: A rare childhood cancer predisposition syndrome caused by biallelic inheritance of mutations in MLH1, MSH2, MSH6, or PMS2 genes. It is characterized by the development of childhood cancers, usually hematological malignancies and/or brain tumors, and colorectal cancers with multiple intestinal polyps. The majority of patients show signs of neurofibromatosis type 1. [1]

Disease Details

Constitutional MMR Deficiency, Biallelic Mismatch Repair Deficiency Syndrome, Constitutional Mis-Match Repair Deficiency Syndrome, CMMR-D, BMMRD, Biallelic Mismatch Repair Deficiency, CMMRD
Hereditary Neoplastic Syndrome


1. National Cancer Institute. NCI Thesaurus Version 18.11d. https://ncit.nci.nih.gov/ncitbrowser/ [2018-08-28]. [2018-09-21].

2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 8. This dataset does not represent the totality of the genetic landscape; see paper for more information.

3. All assertions and clinical trial landscape data are curated from primary sources. You can read more about the curation process here.